Cluster plug



Dec. 16, 1924. I 1,519,498

C.S.MALLETT CLUSTER PLUG.

Filed Aug. 23, 1921 INVENTQR. b QiMaflefi. 3 M5 Patented Dec. 16, 1924-.

UNlTED STATES CHARLES STANLEY MALLE'IT, F TORONTO, ONTARIO, CANADA.

CLUSTER PLUG.

Application filed August 23, 1921.

1' 0 all whom it may concern:

Be it known that I, CHARLES STANLEY MALLETT, a resident of the city ofToronto, in the county of York, in the Province of Ontario, Canada, haveinvented certain new and useful Improvements in Cluster Plugs, of whichthe following is the specification.

My invention relates to improvements in cluster plugs and the object ofthe invention is to so construct the plug that the cover can bemanufactured of insulated material such as porcelain as well as thebase. A further object is to provide means for providing a betterelectrical connection between the lamp screw shells and the main screwplug shell. A still further object is to provide means for preventingthe lamp screw shells from turning relatively to the cover and at thesame time preventing their movmg inwardly.

My invention consists of a cluster plug constructed and arrangedsubstantially as hereinafter more particularly described and illustratedin the accompanying drawing in which:

Fig. 1 represents a side elevation of a cluster plug of the two sockettype constructed according to my invention.

Fig. 2 is a similar view to Figure 1 showing the cover in section.

Fig. 3 is an elevational view of the base of the plug and attached partsviewed at right angles to Figures 1 and 2.

Fig. 4 is a plan view of the cover.

Fig. 5 is an inverted plan view of the base, and

Fig. 6 is a plan view of the main screw plug.

Like characters of reference indicate corresponding parts in thedifierent views.

1 is the base of the cluster plug constructed of suitable insulatingmaterial such as porcelain and provided with the upwardly extendingshank 2 carrying the main screw plug shell 3. a are inwardly extendingteats formed on the top of the main screw plug shell 3 and adapted to beinserted into indentures in the shank 2. 6 are indentures in thevicinity of the lower end of the main screw plug shell 3 adapted to beinsert-ed into corresponding indentures in the shank and to preventlongitudinal displacement of the shell from the shank. 7 is an annulardepending portion formed on the lower face of the base 1 and providedwith the depend ing wedge-shaped boss 8 having two side Serial No.494,566.

walls inclined oppositely at angles of approximately torty-five degrees.9 are correspondingly inclined ridges formed on the inclined walls ofthe boss 8. 10 is a vertical slot formed in one side of the boss 8 andextending up to the lower face of the depending portion 7. 11. is avertical slot extending up through the member 7, through the base 1 andthrough the shank 2 to the top thereof as is shown in dotted lines inFigure 3. It is to be understood that the base 1, the shank 2, dependingportion 7 and the boss 8 are preferably formed integrally one with theother and are constructed of insulating material such as porcelain.

12 is a hollow cover constructed of insulating material such asporcelain and provided with the oppositely inclined annular orifices 13,the inclination of the orifices in the form of cluster plug shown beingap proximately forty-five degrees. let is an annular shoulder formed inthe open top of the cover 12 to receive the depending portion 7 of thebase. 15 are cut-away portions in the cover and 16 are screws forconnecting the cover to the base, as is shown in dotted lines inFigure 1. 17 are lamp screw shells inserted into the orifices 13 in thecover, the shell being provided with a closed flanged base 18 adapted toengage the inner edge of such orifice and also with the slot 19 of thesame shape as the corresponding ridge 9 into which such rid e is adaoted to be inserted.

20 is a tongue of conducting material bent at its lower end toconstitute opposed saddle pieces which are connected to thecorresponding lamp screw shells by means of rivets 22, said saddlepieces being suitably bent to conform in shape to the shape of the lampscrew shells. 23 is a strip of metal, the ends of which are oppositelyinclined, said strip of metal being attached centrally ot' the ridges 9by means of the Vertical screw 2d which extends up through the boss 8,depending portion 7, base 1 and shank 2 to the top of the latter andalso holds in place the contact washer 25, said member 23 being adaptedto constitute the centre contact for the lamp screw shells and to engagethe centre contact of the lamps when they are screwed into the lampscrew shells 17.

From the above description. it will be seen that when my cluster plug 18assembled:

the lamp screw shells 1? will be prevented from turning by the ridges 9entering the slots 19 in the lampscrew shells. Such lamp screw shells 17will also be prevented from moving inwardly by coming into contact withthe inclined walls of the boss 8.

The tongue extending up through the slot 11 is turned over into the formof a hook 26 and soldered to the corresponding teat i, it beingunderstood that the slot 11 communicates with one of the ind'entures 5in the shank and consequently a better electrical connection will bemade.

Hitherto in the construction of cluster plugs it has been the custom tomanufacture the cover of conducting metal such as brass. This presentsthe disadvantage that persons touching the plug are afraid of gettingasl'i'ock and one of the advantages of my conc'on'st'ru'cti on is thatthe cover may be constructed of insulating material such as porcelain.

Many modifications may be made in my invention without departing fromthe spirit of the same or the scope of the claims and the form shown isto be taken in an illustrative and not in a limiting sense. For instanceit would be Within the scope of my invention to so construct the plugthat any number of lamp screw shells will be provided instead of the twoillustrated. This could be done by merely changing the shape of the boss8 to provide inclined walls corresponding to the number of lamp screwshells and to provide the ridges 9 thereon, it then only being necessaryto extend the saddle piece 20 to connect with the flanges of theremaining lamp screw shells.

What I claim as my invention is:

1. In a cluster plug, the combination with the base, of a cover ofinsulating material suitably secured thereto, said cover having l ampscrew shell receiving orifices extending t'l'ierethrough, lamp screwshells freely inserted from the inside of the cover into said orificesand each having an opening in its inner end wall, means bearing againstthe inner end of the shell for preventing its inward movement, andprojections car ried by the bearing means adapted to engage the openingsof the inner end wall of each shell to prevent its turning movement.

, 2. In a cluster plug, the combination with the base constructed ofinsulating material and having a depending boss formed thereon, of acover of insulating material suitably secured to the base, said coverhavrln'g lamp screw shells inserted into said orifices, said shellshaving outwardly extending flanges engaging the inner ends of saidorifices and said boss engaging said flanges for preventing inwardmovement of the shells, said shell flanges having slots therein andridges on the boss inserted into said slots for preventing the turningof the shells in the orifices.

In a cluster plug, the combination with the base of insulating materialhaving a wedgeshaped boss formed thereon, ridges formed on the inclinedwalls of the said boss, a cover of insulating material having inclinedlamp screw shell receiving orifices extending therethrough, lamp screwshells inserted into said orifices having outwardly extending flangeswith lateral slots and closed bases, said bases having lateral slotstherein, said inclined walls engaging said closed bases and the ridgeson said inclined walls inserted into said slots.

4. In a cluster plug, a base of insulating material having an upwardlyextending shank formed thereon, a main screw plug shell on said shank, adepending wedgeshaped boss formed on said base and having ridges on' theinclined walls thereof, a cover of insulating material suitably securedto said base and having inclined lamp screw shell receiving orificesextending therethrough, lamp screw shells inserted into said orifices,each of said shells having a closed base with an outwardly extendingflange engaging the inner edge of the corresponding orifice and alateral slot extending through said closed base, a conducting tongueextending up through said boss, base and shank and connected at itsupper end to the main screw plug shell and means for connecting thelower end of said tongue to the said lamp screw shells.

5. In a cluster plug, a base of insulating material having an upwardlyextending shank formed thereon, a main screw plug shell on said shank, adepending wedgeshaped boss formed on said base and having ridges ontheinclined walls thereof, a cover of insulating material suitablysecured to said base and having inclined lamp screw shell receivingorifices extending therethrough', lamp screw shells inserted into saidorifices, each of said shells having a closed base with an outwardlyextending flangeengaging the inner edge of the corresponding orifice anda lateral slot extending through said closed base, a conducting tongueextending up through said boss, base and shank and connected at itsupper end to the main screw plug shell, the lower end of the tongue bentto constitute a saddle piece suitably secured to the flanges of therespective lamp screw shells.

6. In a cluster plug, a base of insulating material having an upwardlyextending shank formed thereon, a main screw plug shell on said shank, adepending wedgeshaped boss formed on said base and having ridges on theinclined walls thereof, a cover of insulating material suitably securedto said base and having inclined lamp screw shell receiving orificesextending therethrough, lamp screw shells inserted into said orifices,each of said shells having a closed base with an outwardly extendingflange engaging the inner edge of the corresponding orifice and alateral slot extending through said closed base, a conducting tongueextending up through said boss, base and shank and connected at itsupper end to the main scr-ew plug shell, the lower end of the tonguebent to constitute a saddle piece suitably secured to the flanges of therespective lamp screw shells, a central contact screw extending throughthe 10 boss and having its free ends extending 15 through the slots inthe lamp screw shells.

CHARLES STANLEY MALLETT.

